Accessing Keys and Values

Dictionaries in Python store data as key-value pairs. To access specific elements, you can use the following methods:

1. Direct Access:

• Use the key within square brackets to access the corresponding value.

Python

my_dict = {"name": "Alice", "age": 30}

name = my_dict["name"]  # Access the value associated with the key "name"

print(name)  # Output: Alice

2. get() Method:

• The get() method provides a more flexible way to access values. It takes the key as the first argument and an optional default value as the second argument. If the key doesn't exist, it returns the default value.

Python

city = my_dict.get("city", "Unknown")  # Access the value for "city", or "Unknown" if it doesn't exist

print(city)  # Output: Unknown

3. Iterating Over Keys and Values:

• Use the items() method to iterate over key-value pairs.

Python

for key, value in my_dict.items():

    print(key, value)

4. Accessing Keys and Values Separately:

• Use the keys() and values() methods to retrieve the keys and values separately.

Python

keys = my_dict.keys()

values = my_dict.values()

Example:

Python

person = {"name": "John", "age": 35, "city": "New York"}

# Direct access

name = person["name"]

print(name)  # Output: John

# Using get()

age = person.get("age", 0)

print(age)  # Output: 35

# Iterating over key-value pairs

for key, value in person.items():

    print(key, value)

# Accessing keys and values separately

keys = person.keys()

values = person.values()

print(keys)  # Output: dict_keys(['name', 'age', 'city'])

print(values)  # Output: dict_values(['John', 35, 'New York'])

By understanding these methods, you can effectively access and manipulate data within dictionaries in Python.